Finding the Fourth Proportional to 2,287.31, 3,156.49 and 1,239.37

Step by Step Solution

1. Step 1: Write the proportion equation
   2,287.31 : 3,156.49 = 1,239.37 : x
2. Step 2: Convert to fraction form
   2,287.31/3,156.49 = 1,239.37/x
3. Step 3: Cross multiply
   2,287.31x = 3,156.49 × 1,239.37
4. Step 4: Simplify right side
   2,287.31x = 3,912,044.92
5. Step 5: Solve for x
   x = 3,912,044.92/2,287.31
6. Step 6: Final answer
   x = 1,710.33